Apparatus for supplying air to cupola furnaces



May 3l, 1949. H A, REECE 2,471,775

APPARATUS FOR SUPPLYING AIR To oUPoLA FURNAcEs Filed March 24, 1947 ,if f f2 an I N VEN TOR.

Patented May 31, 1949 @UNITED STATES PTE-NT OFFICE APPARATUS FOR SUPPLYING AIR TO CUPOLA FURNACES Herbert A. Reece,` ClevelandfHeights, Ohio ApplicationMarch 24, 194K?,` Serial No. 736,780

(Cl. 26S-30.). i

oneof its objects, aims to provide a novel construction and ymethod of.' operation for a furnace of; this` kind; .Although the novel construction isfhereinafter described in detail by reference toa furnace of the `cupola type, it should be understood that the `invention is intended to include alilwfiurnaces in which air or other gas is delivered into theginterior ofthe furnacethrough tuyres.

In;` cupolas as heretofore constructed the tuyres have `usually been arranged in spaced relation in a series` extending around or partially aroundthe periphery at a level below the melting rzoneand the combustion air` for operating the cupola has beensupplied through a windbox with which the `tuyeres are connectedl In the` operation of the cupola the `quality of the melt and the characteristics of the castings obtained therefrom are dependent upon the attainment of1a uniform condition in the combustion zone.`

Inythe attainmentof such a desired. uniform condition the velocity and volume of air which slag` accumulations will form on the tuyres and series are very important factors.

At times during the operation of a cupola, slag accumulations Willform on the tuyres and Wil-lxpartially restrict the tuyreopenings and` viding the tuyres with individual manually op-` erable dampers which could be closed from time toatime toprevent the slag to be burnedavvay. The main disadvantage accompanying the useof such manually operable dempers is that when a damperis closed by the attendant and is not reopened Within a given time the tuyre and the adjacent metal framework` will become burned and the work of repairing such. damage involves considerable expense as well as an idle repair period for .thecupola The present invention overcomes this diiculty by providing an improved construction by which suchaccumulations of slag on the tuyres is effectively retarded or prevented during the oper-` ation of the cupola.

Another object is to` provide a novel means for supplying air to a furnace through a series of tuyresyin Which a sequential temporary closing of restricting of the air passages to the tuyres, or to groups of tuyres, permits the slag to be burned away-at regular or frequentY time` inter. vals.

Still another Objectis toprovide improved apparatus of this character `in which@mechanically` actuated shutter meansis employedforpausing thetemporary` sequential interrupting o rf-restrict` 4ingfof the air `fiovv to the-tuyres.

Yet another object is to provide improvedapf:v

paratus of thischaraoter` in.; whichthe tuyres are ain groups and the mechanicallyl actuated;

shutter means Aincludes,:shutter elements 'as-u sociated` with the respective `groups and: vvhicl'1uV shutter i elements are vsequentially movable,` to q;

open and closed positions for controlling thesup;l ply of air to the tuyres of such'groups.`

It; is also an object torprovidel improved ape... paratus of this kind in Whichxthe [cupola has sub-` stantially opposed wallsycontaining the groups of tuyres and the `shutter `elements arewactuatedl.

:in such sequence that when the shutter element;`

controllingqthe tuyrespf `one Wall are open or bengopened the shutter element for theytuyresy of` the opposite Wall will be closed.

This invention also provides improved; appa-v .ratus of the kindmentioned in whichqvariableq speed means is employed foroobtainingila .de. sired rate -of actuation `for the-movable:shutten` means.

@ther` objects` and `advantages of the l\inven y tion will become `apparent in thefollowing der;`

tailed description.Y

In the accompanying sheets of drawings:

Figi is a partial end elevational vievv-` show-` ingga furnace of the cupola type embodying the present invention;

Fig. 2 `is a partial transverse sectional .view taken asindicatedby line `l-l of Fig. 1, and

`Fig. 3 isanother partial vertical sectionalview` taken approximately on `line 8 8 of Fig, 2 and 'f showing one of theshutter `actuating devices on a larger scale.

Figs. 1, 2 and 3 shovv` another embodiment `oft` the invention in which'afurnacefor cupola 58 ofi.. the quadrangular type has opposed side Wallsv 59 and `tu. containing` groups `or rows of tuyres` 5.3i `and titwWindboXes 53 and @fi are provided on thesideI Walls lyandll and to which airis sup-4 pl-iedfor delivery to the tuyresfof therespective groupsn The tuyres 6l are supplied with,

air from thelovver endof the vvii'idboxlifthroughy the `cont-rol openingsy 55 which serve the respec-.y`

tive A-tuyres of this group. i A similar` groupvof controlopenings $6 supply air from thelower end `oi the windbox Gil' to the respective tuyres lift of theothergroup.` The controlfopenings 65- andiifof thewindboxes; Stand 6ft are connected with the tuyres fll and 62 `throughthe tuyre.` boxesii'l and til; which are hereshown asgbeing.

laterally continuous for serving all of the tuyres of the groups. If desired, however, the

tial relation and results in the supply of combustion air being delivered into the furnace shaft alternately from opposite sides thereof. This is achieved by temporarily retricting or closing the f control openings o-f one tuyre group while the control openings of the other group remain open, and then reversing this situation.

In the construction as illustrated in Figs. 1, 2 and 3 the openings 65 are controlled by an elongated movable shutter element 10 which is mounted on a pivot shaft 'H and is adapted to swing from a closed position overlying these openings to the upright open position as shown in Figs. 1 and 2 in which the openings are uncovered. Similarly the openings 66 are controlled by a movable shutter element 12 mounted on a pivot shaft 13. Any appropriate mechanism can be employed for causing the shutters 10 and 12 to be actuated in the desired alternate or sequential relation so that each shutter will be moved to an open position while the other shutter remains closed or restricted.

One suitable form of actuating mechanism for the shutters 10 and 12 is here shown as comprising gear-like disk members 1A and 15 which are adapted to be continuously driven in opposite directions by worm elements 16 and 11 carried by a common actuating shaft 13. This shaft is driven by a variable speed electric motor 19 through the gear 60 and motor pinion 9|. The pivot shafts 1l and 13 of the shutters 10 and 12 have actuating levers 82 and S3 mounted on the ends thereof which are adjacent to the disks 14 and and these levers carry projecting pins 84 and 85. The disks 'M and 15 have lugs 96 and 81 mounted thereon which, during rotation of the disks by the worm elements '16 and 11, engage the pins 84 and 95 to cause swinging of the levers 82 and 63 for temporarily moving the shutters 10 and 12 t0 the open position.

The disks 14 and 15 are mounted for rotation on shafts 14a and 15a which are disposed in eccentric relation to the axes of the pivot shafts 1! and 13 of the shutters 1i) and 12. Because of the eccentric mounting of these disks relative to the pivot shafts, the lugs 86 and4 81 Will have paths of travel such that they will engage and pick up the pins 3d and 85 at points corresponding with the closed positions of the shutters 10 and 12 and will swing the levers 82 and 83 to a substantially upright position corresponding With the open condition of the shutters. During this upward swinging of the levers the pins 84- and 85 will slide across the faces of the lugs 86 and 81 and when the levers approach or reach their vertical position the levers will be released by reason of the lug-s being carried over the pins. As shown in Fig. 1, the disks 14 and 15 have the actuating lugs 33 and 81 thereof spaced apart approximately 180 so that the opening of the shutters which is produced by the upward swinging of the levers 82 and 83 as jlust described, will take place in the desired sequential or alternate relation. It will be understood of course that the above described actuation of the shutters is carried out as a continuous cycle and that as soon a-s one c-f the lugs has lifted the corresponding shutter and has released the pin, that shutter will drop by gravity to its closed position overlying the control openings.

The rate at which the alternate or sequential actuation of the shutter-s 10 and 12 is carried out can be varied so as to provide a time interval of desired length during which the tuyres of each group will be supplied with air. This can be accomplished by varying the speed of the electric motor 19 as by means of the speed control device or rheostat 90. The shutter actuating disks 14and 15 and the electric motor for driving the same can be mounted on any suitable support, such as the bracket 9i, which is attached to the shell of the furnace structure. From the construction illustrated in Figs. 1, 2 and 3, and described above, it will be seen that combustion air will be supplied to the furnace shaft alternately from opposite sides thereof through the tuyre groups 6| and 62 and when one group of tuyres is temporarily closed, any slag accumulation thereon will be effectively melted off or burned away.

From the accompanying drawings and the foregoing description it will now be readily understood that this invention provides a novel apparatus by which the air supply to the tuyres of a furnace can be controlled so as to cause a temporary sequential decrease or interruption in the flow of air to the tuyres or to groups of tuyres for preventing slag accumulations on the tuyres during the operation of the furnace. It will also be understood that the invention provides a continuously operating, variable speed shutter mechanism by which the sequential temporary closing or restricting of the air passages to the tuyres or groups of tuyres can be obtained in a practical and dependable manner.

Although my invention has been illustrated and described herein in some detail it will be understood, of course, that the invention is not to be regarded as being correspondingly limited but includes all changes and modications coming within the scope of the appended claim,

Having thu-s described my invention, I claim:

A cupola having a rectangular shaped shaft having a separate windbox on each of two opposite sides, each windboX having a set of tuyres, an air supply means to each windbox, a movable shutter means in each windbo-X between the air inlet and tuyres thereof, and mean-s for operating said shutter means to alternately retard or shut off the flow of air through the tuyres of each windbox.

HERBERT A. REECE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,092,623 Zppler Apr. '7, 1914 1,668,133 Weichel May 1, 1928 2,295,604 Reece Sept. 15, 1942 FOREIGN PATENTS Number Country Date k533,922 Germany Sept. 19, 1931 

